Dental bridgework



. D. S. HIGHKIN.

DENTAL BRIDGEWORK.

APPLlCATION FILED MAY 7. 1920.

Patented July 6, 1192).

. intense.

Toull whom it may concern:

, illustrated NITED sTA'rss PATENT UFHfiE.

:navIn s. Hle'rrikiri, or BALTIMORE, iraavnaivn.

nniv'rar. nninenwonir.

lieit known that l, IDAVID a citizen of the United States,res1ding at Baltimore, in the State of Maryland, have invented certain new and. useful Improvementsin Dental Bridgework,of which the followingis a specificatlon.

The present invention relatesto dental bridgework, and more particularly for. an

The preferred form of construction is.

in the accompanying drawings,

wherein Figure 1 is'a front elevation of the facing,

Fig. 2 is an edge view thereof,

Fig. 3 is a vertical sectional View,

Fig. 1 is a. rear elevation, y y

Fig. 5 is a frontelevation of the backing,

Fig. 6 is an edge View of thesame,with the solder in place, i

Fig. 7 is a vertical sectional view through Fig.6, v i

Fig. 8 is a vertical sectional view through the backing without the solder,

Fig. 9 is a rear elevation of the assembled facing and backing,

a Fig. 10 is a vertical sectional view through a completed bridge, and

Fig. 11 is a rear elevation of a portion of a bridge with parts broken away,

Fig. 12 is a vertical sectional view through a modified facing during the process of con struction,

Fig. 13 is a similar viewof the completed tooth illustrated in Fig. 12.

111 the embodiment illustrated in Figs. 1-11 inclusive the facing is designated 1a and is preferably porcelain, with front and rear faces, the main portions of which are substantially parallel, and tapered inner and outer ends 15 and 16. Embedded in the central portion of the facing, and extending to the rear face thereof, is a socket piece 16 that is internally threaded, as illustrated at 17. Alongside this socket piece a socket 18 is formed in the facing.

The backing is designated 19 and is preferably a relatively thin sheet of metal, as

i specification of Letters Patent. i Application filed May 7, 1920. Serial No. 379,569.

HIsI-IKIN,

end portions of the Patented July 6, 1920..

gold, having offset end margins 20 and 21 that conformto the correspondingly shaped rear face of the facing 14%. The backing is provided with a centrally disposed rearwardly extending enlargement or boss 22 provided with an open- 111g 23 therethrough that alines with the socket 16 and has its rear end countersunk as shown at 24.. The backing furthermore is provided with a positioning stud 25 carried by the boss and adapted to engage in the socket1l8 when the backing is in place,

as shown more particularly in Fig. 10.

It will be evident particularly by reference to Fig. 10 that the backing conforms 1 to and'iits throughout its extent against the rear face of the facing 14 and is held in place by a headed screw 26 that passes through the opening 23 and is screwed into the socket piece 16, the head of said screw entering the countersunk portion 24 of said opening The two elements or members are thus effectively held together. In using the teeth for bridge-work, a series of them are placed edge to edge and the backings are connected by the usual solder 27 that extends over the various backings, bridging the joints between them and being flush with :the rear end or face of each boss, thus leaving the heads of the screws 26 exposed and available, as shown in Fig. 11.

This structure has various advantages. In the first place, it will be clear that each facing is effectively supported and yet practically no metal is exposed to view, thereby producing a most natural appearance. An

facing however, may be detached from the bridge by removing the screw 26 which holds it in place, so that if one is defaced or injured, it may be substituted by another without difficulty and without the necessity of working over or altering the bridge. Moreover a bridge constructed as above described utilizes but very little metal, and

can be easily and expeditiously manufactured, thereby saving expense in both time and material.

As is well known to those skilled in the art, platinum is the best metal available for embedment in porcelain facings, and the socket pieces 16 therefore are preferably made of this material. Platinum, however, is very expensive and if desired the threads to engage with the screw may be formed integral with the facing element itself. Thus, as illustrated in Figs. 1 2 and 13, the

-facing element designated 14 and is Thereforewheir a screw is threaded'therebaked, with a threaded plug of'platinu n 16" embedded therein. After the facing is completed this plug of platinuni may be removed in any suitable manner. For example, it can be dissolved by chemicals, such" as aqua regia, the platinum being afterward recovere'd by'precipitation in a Well known I manner. This therefore leaves the-socket with the threads 17 formed of and directly in the porcelain facing, as shown in Fig. 13.

into and cemented, it will, effectively hold the facing to the backing.

V Fronnthe foregoing, it is thought that the,

construction, operation and many advantages ofthe herein described invention Wlll beapparentto those skilledin the art, with- V V 1 In dental bridgework, a facing proout further description, and it will be understood that various changes in thejsize, shape, proportion and mlnor details of construct1on,1n ay be resortedto without departing from the spirit or sacrificing any of the Y advantages of the invention.

Havingthus, fully described my invention, WhatI clai n as new, and desire to secure by Letters Patent, is

videdwith a threaded socket in its rear side and a second socket alongside the same, a backlng having an opening that alineswlth the threaded socket, ancha projection that.

enters the second socket, and a screw that passes through said opening in the backing and engages .in thethreaded socket to hold theb'acki-ng and-facing together;

V 2, In dental bridgework,; a facing pro-V vided with spaced sockets in its rearside, a 1 T backingithat fits against the rear side of the facingande is providedwith a rearwardly extending boss and a forwardly extending positioning stud that enters one of the sockets, and a device for holding the facing to the backing, engaging said backing and entering the other socket.

'3. In dental bridgework, a facing provided with a threaded socket in itsrear side and a second socket alongside the same, a

backing having a rearwardly extending boss provided with an opening that alines with the threaded socket and a projection that enters the second socket, and a screw that passes through saidopening in the backing and engages in the threaded socket to hold the'backing and facing together.

4. In dental bridgework, a plurality of Vfacings provided with threaded sockets in the socket piece, a backing having an open ing that alines with the bore of the socket piece and a stud that enters the socket, and Ya screw that passes through the opening and is threaded into the socket piece.

In testimony whereof I afiix my signature.

DAVID S. HIGHKIN. 

